American Journal of Electrical and Electronic Engineering
ISSN (Print): 2328-7365 ISSN (Online): 2328-7357 Website: Editor-in-chief: Naima kaabouch
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American Journal of Electrical and Electronic Engineering. 2016, 4(6), 157-163
DOI: 10.12691/ajeee-4-6-2
Open AccessArticle

Analysis of Transformer Loadings and Failure Rate in Onitsha Electricity Distribution Network

Hachimenum N. Amadi1, and Fabian I. Izuegbunam1

1Department of Electrical & Electronic Engineering, Federal University of Technology, Owerri, Nigeria

Pub. Date: December 22, 2016

Cite this paper:
Hachimenum N. Amadi and Fabian I. Izuegbunam. Analysis of Transformer Loadings and Failure Rate in Onitsha Electricity Distribution Network. American Journal of Electrical and Electronic Engineering. 2016; 4(6):157-163. doi: 10.12691/ajeee-4-6-2


This study investigated transformer loadings and failure rate in the Onitsha Electricity Distribution Network by using the Electrical Transient Analysis Program (ETAP) software 12.6 and the Statistical Package for the Social Sciences (SPSS) software 16.0. Data collected over the period 2011-2015 on the distribution network were simulated on ETAP software using the Newton-Raphson (N-R) technique to determine the transformer loadings while responses to 350 copies of questionnaire distributed among the technical staff were statistically analysed on the SPSS software to ascertain the failure rate among transformers in the network. The findings of the study show that during the 5 years period covered by the study, the sampled substations recorded transformer average failure rate of 11.7 %. It was further revealed that besides insulation issues which accounted for 24.2% of all the failures, overload (22.5%) was the next major cause of transformer breakdowns in the distribution network. The study recommends installation of more transformer units, use of high quality transformers, balanced loading of the transformers and proactive inspection and maintenance program of transformers units within the network. The outcome of this work would help electricity utilities provide more reliable and cost effective services to customers.

distribution network electricity supply failures failure rate transformer failure transformer loading

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